Method of producing tobacco foils



United States Patent 3 288 148 METHOD OF PROliUCiNG TOBACCO FOILS Ernst-Rolf Detert, Lubhecke, and Willi Buchholz, Obermehnen, near Lubhecke, Germany, assignors to Eduard Gerlach G.m.b.H., Westphalia, Germany No Drawing. Filed June 1, 1964, Ser. No. 371,742 Claims priority, application Germany, June 14, 1963,

1 Claim. (Cl. 131-140) The present invention relates to a method of producing tobacco foils, particularly for use as wrappers as a substitute for natural tobacco leaves.

Such tobacco foils, also called homogenized tobacco leaves are frequently used in the manufacture of cigars as a cove-ring for holding the tobacco together. They are made by mixing pulverized tobacco with binding agents on a basis of cellulose ether or cellulose ester which are soluble in water or in organic solvents. The cigars which are covered by such tobacco foils are then wound up in wrappers in the form of natural tobacco leaves and there-afiter they are sorted, pressed, and packed. Because of the nature of such natural Wrappers it is sometimes necessary to treat the wrapped cigars with socalled moist powders or color dulling agents in order to improve glowing and burning properties as well as the appearance of the cigars. Thus, for example, the wrapper-enclosed cigars are covered with a very thin layer of moist powder which is fixed so as to be saliva proof by means of a solution of cellulose derivatives which are insoluble in Water, especially ethyl cellulose.

Since the mechanical properties of such tobacco foils are much more suitable than those of natural tobacco leaves and facilitate the cigar production considerably, these foils have also been used as wrappers. It has, however, been found that the tobacco foils which are made in accordance with the method as described above lack in various properties which are regarded as essential in high-grade Wrappers. This means that prior to this invention it has in most cases been absolutely necessary to subject the otherwise finished cigars to an additional treatment with the determined moist powders and dulling agents.

It is the principal object of the present invention to provide a very simple method which permits such an afte-rtreatment of the otherwise finished cigars which are covered with tobacco-toil wrappers to be omitted by incorporating the required substances for improving the glowing or smoldering properties and the color and appearance of the cigars in the tobacco foils in the course of their production.

These substances should be selected in accordance with the following requirements: The pigments to be employed should have a good covering power but be physiologically without any objections and entirely harmless. The coloring substances which are subjected in the smoldering zone to a thermal decomposition process should burn up as completely as possible into CO and H 0 without leaving any cleavage products consisting of aromatic amines, polycyclic hydrocarbons, or other carbonizing substances.

According to the invention it has been found and proved by smoldering tests in which the smoldering process proceeded in the same manner as in the wrapper of a cigar that vegetable pigments of the series of flavones and antho-cyanins in a lacquered form by being combined with whiteners such as calcium carbonate, magnesium carbon-ate, aluminum hydroxide, talc, or titanium Patented Nov. 29, 1966 dioxide are particularly suitable for the purposes of the invention. These tests have shown that, since the substances employed do not contain any aromatic nitrogen but are only composed of the elements carbon, hydrogen and oxygen, they fully comply with the requirement of a complete combustion into CO and H 0 which is made for physiological reasons. This effect was entirely unexpected especially since it was so far assumed that the pigments are only loosely bound by adsorption by the carbonates and hydroxides which are employed for the lacque-ring process. The fact that the pigment molecules will not sublime in the smoldering zone of the cigar could certainly not be foreseen by the knowledge as derived from the state of the prior art.

In the mentioned smoldering tcsts it was found that when "unlacquered pigments of the series of flavones and anthocyanins are smoldering, pigment components occur in the smoke which should be avoided under any circumstances. This may be definitely ascertained by an adsorption test on layers of paper.

For attaining the object of the invention, that is, to produce dyed tobacco foils with the desired smoldering properties, the most suitable materials are lacquers made of buckthorn berries extract and haematein.

The following example may serve as an illustration of the procedure to be followed in carrying out the inventive method and of the required quantities of the various materials needed for producing a tobacco foil according to the invention:

5 g. of potassium hydroxide are dissolved in 1 liter of distilled water and 0.5 g. of buckthorn berries extract and 10 g. of titanium dioxide are added while the mixture is heated to centigrade and stirred. While the stirring is continued a 5% solution of aluminum sulphate is slowly instilled until the liquid has a pH of 6. The largest proportion of the water is then drawn off by suction whereupon the filtered residue is washed in water until the-re is no longer any sulphate reaction in the water and the pure aluminum lacquerprecipitated on titanium dioxideis attained. The amounts of the materials as stated result in 7.38 g. of colored lacquer which contains approximately 7% of coloring matter.

A suitable proportion of the lacquer which is thus produced is then added either in a moist or dried and pulverized condition to the paste consisting of pulverized tobacco cellulose ethers and solvents, so that, when the paste is thereafter spread out and dried, the finished tobacco foil has the appearance of a high-grade wrapper which requires no further treatment after being wrapped on a cigar.

Although our invention has been illustrated and described with reference to the preferred embodiments thereof, we wish to have it understood that it is in no way limited to the details of such embodiments, but is capable of numerous modifications within the scope of the appended claim.

Having thus fully disclosed our invention, what we claim is:

A method of producing tobacco foils comprising the steps of mixing finely pulverized tobacco with a viscous solution of cellulose derivatives in a solvent of a group consisting of water, organic solvents, and mixtures thereof so as to form a paste, mixing at least one whitener of the group consisting of calcium carbon-ate, magnesium carbonate, aluminum hydroxide, talc, and titanium dioxide with at least one vegetable pigment of the group consisting of flavones and anthoeyanins so as to form a colored lacquer, adding said lacquer to said 3 paste, then shaping the mixture into foils, and drying said foils.

References Cited by the Examiner UNITED STATES PATENTS 2,930,719 3/1960 Finbeng 131-17 3,003,895 10/1961 G-runwald 131-17 7 4 7 OTHER REFERENCES Principles of Bio Chemistry by White, Handler and Smith (3rd Ed.), published -by McGraw Hill (N.Y.), 1959, page 46 esp. cited.

SAMUEL KOREN, Primary Examiner.

MELVIN D. 'REIN, Examiner. 

